Suggestions for 150g rr tank

In my experience at least, UGF's are not low-maintenance in planted or heavily stocked tanks. Waste/mulm may accumulate beneath the plate more rapidly than the bacteria consume it, eventually becoming anoxic sludge; once this happens you have to tear apart your aquascaping to clean it. I would definitely go with a sump over a UGF. Besides ease of maintenance, another advantage is that you can include a macroalgae-planted refugium, reducing algal growth in the main tank.

If you're going for a planted biotope, the easiest options are Amazon, South/Southeast Asian, and East/Central North American; fewer plants are available from other parts of the world. There are plenty of gorgeous community fish from each region.

The Amazon has tetras, hatchets, silver dollars, plecos, otos, cories, numerous other cats, etc.

Southeast Asia has rasboras, barbs, danios, gouramis, loaches, glassfish, and cats such as Mystus and glass cats.

North America has darters, shiners, dace, madtoms, mollies, killifish, pygmy sunfish, true sunfish, crayfish, and flagfish.
 
Thinking that planted is the way to go. Like I said, the tank already have t5s and I have an expensive reef CO2 system ... so I could go b*lls out planted without too much real expense. I like the idea of plants and a HUGE number of smaller fish (neons) with some discus or something as showpiece fish.

I *never* did weekly water changes when I kept freshwater. Maybe once every 3-6 months if the tank was lucky, and everything did just fine. Would a sump serve as well as the canister?
 
Yeah, if anything a sump is better (more room for media); it's just more of a hassle to set up than plug-in-and-go canisters. Planted tanks don't need as rigorous a water change schedule as unplanted tanks, but they still need regular wc's. My planted, lightly-stocked 65 gets a 25% wc every other week.
 
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